The eye is a complex system of highly differentiated tissues of various developmental origins. Many genes essential for eye function are tissue-specific and many of those known are associated with genetic eye diseases. The majority of human expressed genes are known only through expressed sequence tags (ESTs). A project called NEIBank was begun to improve the EST coverage and to develop a molecular encyclopedia for the eye (http://neibank.nei.nih.gov). Many human eye (and also ear)tissues and those of important animal models have now been analyzed. Recent additions are human and mouse lacrimal gland, keratoconus cornea, mouse retina and RPE and several libraries from dog, rabbit and zebrafish tissues. The human DNA resource generated by this work has been used to create cDNA microarrays with 13,000 non-redundant human eye expressed sequences and 6500 sequences from mouse eye. This database is also an important source of gene discovery. Several genes are under further investigation, including lengsin, a marker for terminal differentiation in the lens; PDGF-D, a important mitogen for lens development that is secreted into the aqueous humor and is also expressed in the outer plexiform layer of the retina; retbindin a candidate carotenoid binding protein of the retina; and a novel cornea-specific gene that may be associated with stem cell populations. Mouse models for the function of these genes are being developed using "recombineering" technology. A recent addition to the informatics tools for eye research is EyeBrowse, a dedicated genome browser for eye-expressed genes, produced in collaboration with CIT. http://eyebrowse.cit.nih.gov/genome/